"Creation rather than painting, or if painting, yet such, and with such co-presence of the whole picture flash'd at once upon the eye, as the sun paints in a camera obscura. (Describing his poetic ideal, 1817)"

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Considering that knowledge of the chemical as well as the optical principles of photography was fairly widespread following Schulze's experiment (in 1725)... the circumstance that photography was not invented earlier remains the greatest mystery in its history... It had apparently never occurred to any of the multitude of artists of the seventeenth and eighteenth centuries who were in the habit of using the camera obscura to try to fix its image permanently.

— Helmut Gernsheim